Cutting arrangement having a tip-to-tip blade arrangement

Abstract

A cutting arrangement for longitudinally cutting material includes two blades disposed across from one another and which cooperate during cutting. Each blade is embodied as a circular blade having a sharp cutting edge and supported by an adjusting or placement mechanism. During the cutting process, the circular blades are positioned by the adjusting or placement mechanisms so that the cutting edges overlap one another to form an overlap zone, the center of which coincides with the middle of the material that is to be cut. An adaptive control assembly includes individual drive motors for driving each blade and enables constant side load force control for each blade, such that side load pressures are adjustable in response to changes in web sped, web tension, and blade condition in real time. Automatic blade diameter sensors calculate the zero point of the cut, determine the appropriate blade speed and automatically set the overlap.

We claim: 
     
       1. A method for longitudinally cutting or dividing material, comprising the following steps:
 providing a cutting assembly comprising two blades that are disposed across from one another and that during a cutting process cooperate with one another, wherein each of said blades is embodied as a circular blade having a sharp cutting edge and supported by an adjusting or placement mechanism; 
 cutting said material, wherein during said cutting said circular blades are positioned by means of said adjusting or placement mechanisms in such a way that said cutting edges overlap one another to form an overlap zone and a center of said overlap zone coincides with a middle of the material that is to be cut or divided; and 
 providing an adaptive control assembly configured for compensating load fluctuations, said adaptive control assembly comprising separate, individual drive motors for driving each of the two blades; means for constant side load force control; and blade diameter sensors for sensing automatically a respective diameter of said blades, 
 matching rotational surface speeds of said blade; and 
 setting differential speeds for said blades via said individual drive motors. 
 
     
     
       2. A method for longitudinally cutting or dividing material, comprising the following steps:
 providing a cutting assembly comprising two blades that are disposed across from one another and that during a cutting process cooperate with one another, wherein each of said blades is embodied as a circular blade having a sharp cutting edge and supported by an adjusting or placement mechanism; 
 cutting said material, wherein during said cutting said circular blades are positioned by means of said adjusting or placement mechanisms in such a way that said cutting edges overlap one another to form an overlap zone and a center of said overlap zone coincides with a middle of the material that is to be cut or divided; 
 providing an adaptive control assembly configured for compensating load fluctuations, said adaptive control assembly comprising separate, individual drive motors for driving each of the two blades; means for constant side load force control; and blade diameter sensors for sensing automatically a respective diameter of said blades; 
 monitoring of a blade side force and adjusting in real time side load pressures in response to changes in web speed, web tension, and blade condition by said means for constant side load force control; and 
 automatically calculating a zero point of a cut, automatically determining a blade speed for said blades that is suitable for said material being cut, and automatically setting the overlap zone by said blade diameter sensors. 
 
     
     
       3. A method for longitudinally cutting or dividing material, comprising the following steps:
 providing a cutting assembly comprising two blades that are disposed across from one another and that during a cutting process cooperate with one another, wherein each of said blades is embodied as a circular blade having a sharp cutting edge and supported by an adjusting or placement mechanism; 
 cutting said material, wherein during said cutting said circular blades are positioned by means of said adjusting or placement mechanisms in such a way that said cutting edges overlap one another to form an overlap zone and a center of said overlap zone coincides with a middle of the material that is to be cut or divided; 
 providing an adaptive control assembly configured for compensating load fluctuations, said adaptive control assembly comprising separate, individual drive motors for driving each of the two blades; means for constant side load force control; and blade diameter sensors for sensing automatically a respective diameter of said blades; and 
 automatically calculating a zero point of a cut, automatically determining a blade speed for said blades that is suitable for said material being cut, and automatically setting the overlap zone by said blade diameter sensors. 
 
     
     
       4. A cutting arrangement for longitudinally cutting or dividing material, comprising:
 two blades that are disposed across from one another and that during a cutting process cooperate with one another, wherein each of said blades is embodied as a circular blade having a sharp cutting edge and supported by an adjusting or placement mechanism, wherein during a cutting process said circular blades are positioned by means of said adjusting or placement mechanisms in such a way that said cutting edges overlap one another to form an overlap zone and a center of said overlap zone coincides with a middle of the material that is to be cut or divided; and 
 adaptive control assembly configured for compensating load fluctuations, said adaptive control assembly comprising separate, individual drive motors for driving each of the two blades; means for constant side load force control; and blade diameter sensors for sensing automatically a respective diameter of said blades, 
 wherein said means for constant side load force control are configured for monitoring of a blade side force and to adjust in real time side load pressures in response to changes in web speed, web tension, and blade condition, and 
 wherein the blade diameter sensors are configured to automatically calculate a zero point of a cut, to automatically determine a blade speed for said blades that is suitable for said material being cut, and to automatically set the overlap zone. 
 
     
     
       5. A cutting arrangement for longitudinally cutting or dividing material, comprising:
 two blades that are disposed across from one another and that during a cutting process cooperate with one another, wherein each of said blades is embodied as a circular blade having a sharp cutting edge and supported by an adjusting or placement mechanism, wherein during a cutting process said circular blades are positioned by means of said adjusting or placement mechanisms in such a way that said cutting edges overlap one another to form an overlap zone and a center of said overlap zone coincides with a middle of the material that is to be cut or divided; and 
 adaptive control assembly configured for compensating load fluctuations, said adaptive control assembly comprising separate, individual drive motors for driving each of the two blades; means for constant side load force control; and blade diameter sensors for sensing automatically a respective diameter of said blades, 
 wherein the individual drive motors are adapted to enable rotational surface speed matching and differential speeds of said blades, and 
 wherein the blade diameter sensors are configured to automatically calculate a zero point of a cut, to automatically determine a blade speed for said blades that is suitable for said material being cut, and to automatically set the overlap zone. 
 
     
     
       6. A cutting arrangement for longitudinally cutting or dividing material, comprising:
 two blades that are disposed across from one another and that during a cutting process cooperate with one another, wherein each of said blades is embodied as a circular blade having a sharp cutting edge and supported by an adjusting or placement mechanism, wherein during a cutting process said circular blades are positioned by means of said adjusting or placement mechanisms in such a way that said cutting edges overlap one another to form an overlap zone and a center of said overlap zone coincides with a middle of the material that is to be cut or divided; and 
 adaptive control assembly configured for compensating load fluctuations, said adaptive control assembly comprising separate, individual drive motors for driving each of the two blades; means for constant side load force control; and blade diameter sensors for sensing automatically a respective diameter of said blades, 
 wherein the blade diameter sensors are configured to automatically calculate a zero point of a cut, to automatically determine a blade speed for said blades that is suitable for said material being cut, and to automatically set the overlap zone. 
 
     
     
       7. The cutting arrangement according to  claim 4 , wherein the material is composed of a length of material having a given material thickness, and wherein said circular blades are positioned in such a way that the center of said overlap zone is disposed in the middle of said material thickness of said length of material. 
     
     
       8. The cutting arrangement according to  claim 4 , wherein the material that is to be cut or divided is composed of a stack of individual lengths of material, and wherein said circular blades are positioned in such a way that the center of said overlap zone is disposed in the middle of the overall material thickness of said stack of lengths of material. 
     
     
       9. The cutting arrangement according to  claim 4 , wherein respective sensors for detecting or determining said overlap zone are disposed on said adjusting or placement mechanisms for said circular blades and are coupled with control devices for respective adjustment movements of said circular blades. 
     
     
       10. The cutting arrangement according to  claim 4 , further comprising a fixation device that is adapted to feed the material that is to be cut or divided to said circular blades, wherein a lower one of said blades extends beyond an upper edge of said fixation device by an amount that is to be set in conformity with a material thickness of the material that is to be cut or divided and to said overlap zone of said circular blades. 
     
     
       11. The cutting arrangement according to  claim 10 , wherein said fixation device is embodied as a fixation or guide table that is adapted to support the material that is to be cut or divided. 
     
     
       12. The cutting arrangement according to  claim 10 , wherein said fixation device is embodied as a fixation roller over which the material that is to be cut or divided is adapted to be guided. 
     
     
       13. The cutting arrangement according to  claim 9 , wherein said control devices for the adjustment movements of said circular blades are connected to an input unit for the material thickness of the material that is to be cut or divided. 
     
     
       14. The cutting arrangement according to  claim 4 , further comprising a device for determining or detecting the material thickness of the material that is to be cut or divided, wherein said device is disposed upstream of said circular blades and is connected to control devices for adjustment movements of said circular blades. 
     
     
       15. The cutting arrangement according to  claim 4 , further comprising a fixation device for support or feeding of the material that is to be cut or divided to said circular blades and a device for determining or detecting the material thickness of the material that is to be cut or divided, wherein said device is disposed on said fixation device.